1. Field of the Invention
The present invention relates to electronic printers and printing systems, and more particularly, to a method of monitoring the number of times a job concurrently active with other jobs in the system crashes.
2. Description of the Related Art
In electronic reprographic printing systems, a complex series of interactions occurs between the software services and objects and the hardware functions to provide the printed or otherwise processed end-product. In such a system, a document or series of documents comprising at least one print job are successively scanned, resulting in image signals which are electronically stored. The signals are later read out successively and transferred to a printer for formation of the images on paper. Such a document can be printed any number of times or processed in any number of ways (e.g., words deleted or added; image magnified or reduced, etc.). If a plurality of documents comprise a job which is being processed, the processing or manipulation of the documents can include deletion of one or more documents, reordering of the documents into a desired order, or addition of a previously or subsequently scanned document or documents. The printing or processing can be relatively synchronous with scanning, or asynchronous after scanning. If asynchronous, a time interval exists between scanning and printing or processing. The system can then accumulate a number of scanned jobs in the system for subsequent processing or printing. The order of the jobs to be printed may be different from the order of jobs as scanned depending on the priority of the jobs and the desires of the operator for increasing productivity or through-put and decreasing printer or scanner downtime.
In such a system, faults on all levels of functioning at some time during the system's operation can occur. Software object faults may occur to result in such problems as software/hardware errors, illegal job parameters, corrupted data, resource problems, input master errors, font problems, etc. Mechanisms for dealing with such faults are an integral and necessary component of the system, because such faults will result in the interruption of the system's operation and may result in a crash of the system which requires that the system be rebooted. Information from the system provided to the operator directing the operator to the fault or faults causing the job interruption is critical to the efficient operation of the system.
An important item of information is the number of times a fault occurs in the system. One method of acquiring and supplying this information to the operator is by recording the faults in a log. By doing so, a threshold number of faults can be established and used to determine the need for further diagnostic action on the system.
In a similar manner, it is important for the system to keep track of the number of times that a system crashes along with a record of the jobs which are concurrently active within the system at the time of the crash. Such information is valuable to an operator because it may enable the operator to remove the source of the crash, which is itself immediately disruptive to the work being performed by the system, without requiring the system to cycle-down in order to resolve the source of the crash. Such a procedure requires a rebooting of the system, which is time-consuming and significantly decreases the efficiency of the system.
The related art has disclosed printing systems which contain systems for identifying, counting and evaluating errors.
U.S. Pat. No. 4,866,712 to Chao discloses a table-driven recovery control system for computers wherein a data table records all identified errors in an error table, and all corrective actions in an action table. The table includes a count increment for each action in response to an error and such counts are accumulated until a count threshold is exceeded, at which time a corrective action is initiated.
U.S. Pat. No. 4,339,657 to Larson et al. discloses a control system which supplies command signals to initiate system functions and which has a means for producing error signals that indicate malfunctions of the system. An error counter responds to error signals to provide a count value representing the total number of error signals which have occurred. Additionally, a sensing means produces a value signal when the error count exceeds a given value.
U.S. Pat. No. 4,745,602 to Morrell discloses a printer error and control system wherein the printer provides a specific error status indication to the system host. The error signals comprise fatal and nonfatal classes of system errors. Upon the occurrence of certain nonfatal errors, the host computer may invoke a procedure to reset the data output device and adjust its output data flow to provide a corrective measure.
U.S. Pat. No. 4,908,811 to Yokogawa et al. discloses a method for recording and reproducing data with error reduction. An error ratio is calculated which, when greater than a predetermined value, adjusts a delay circuit.
While the prior art provides for the recordation of errors in various computer and reproducing systems, and for the system's response when the recorded errors reach a threshold level, the prior art fails to disclose a program within the system which provides the operator with the instructions and means by which the job within the system causing the problem can be determined without requiring the system to cycle-down. It is desirable for a system to have a corrective mechanism programmed within it which interacts with the operator, and permits the operator's judgements to be factored into such decisions as deletion of jobs or data in the system in order to effect recovery as efficiently as possible.